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How do I check if a column is empty or null in MySQL?
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This will select all rows where some_col is NULL or '' (empty string)
SELECT * FROM table WHERE some_col IS NULL OR some_col = '';
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Converting many 'if else' statements to a cleaner approach [duplicate]
...ng this approach you could easily add different converters in the future.
All untested, probably doesn't compile, but you get the idea
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What is NoSQL, how does it work, and what benefits does it provide? [closed]
I've been hearing things about NoSQL and that it may eventually become the replacement for SQL DB storage methods due to the fact that DB interaction is often a bottle neck for speed on the web.
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Why doesn't .NET/C# optimize for tail-call recursion?
...n was responsible for the machine code.
The CLR itself does support tail call optimization, but the language-specific compiler must know how to generate the relevant opcode and the JIT must be willing to respect it.
F#'s fsc will generate the relevant opcodes (though for a simple recursion it may j...
How do I get a plist as a Dictionary in Swift?
...want to shift focus to swift soon, but currently the swift APIs don't have all the functionality of the core NSClasses.
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How to add custom method to Spring Data JPA
... looking into Spring Data JPA. Consider the below example where I will get all the crud and finder functionality working by default and if I want to customize a finder then that can be also done easily in the interface itself.
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Getting the client's timezone offset in JavaScript
...ant even for a given locale
Mozilla Date Object reference
Note that not all timezones are offset by whole hours: for example, Newfoundland is UTC minus 3h 30m (leaving Daylight Saving Time out of the equation).
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jQuery set checkbox checked
I already tried all the possible ways, but I still didn't get it working.
I have a modal window with a checkbox I want that when the modal opens, the checkbox check or uncheck should be based on a database value. (I have that already working with others form fields.) I started trying to get it c...
Most efficient way to increment a Map value in Java
...s folks--so I decided to run some tests and figure out which method is actually fastest. The five methods I tested are these:
the "ContainsKey" method that I presented in the question
the "TestForNull" method suggested by Aleksandar Dimitrov
the "AtomicLong" method suggested by Hank Gay
the "Trove...
What is the MySQL VARCHAR max size?
...er is subject to the maximum row size (65,535 bytes, which is shared among all columns) and the character set used.
However, note that the limit is lower if you use a multi-byte character set like utf8 or utf8mb4.
Use TEXT types inorder to overcome row size limit.
The four TEXT types are TINY...